Effect of Natural Fermentation on the Functional Properties of Protein-Enriched Composite Flour

The functional properties of a naturally fermented composite flour made up of 30% edible defatted groundnut flour and 70% sorghum meal were compared with conventionally fermented sorghum meal. Fermentation increased the nitrogen solubility of the composite flour in the alkaline pH region. The increased protein of the composite flour (23%) improved the functionality of the meal as reflected in its better water-absorption capacity, its water-retention capacity, and its fat-absorption capacity compared to values obtained with sorghum meal for the three functional properties, respectively. Natural fermentation resulted in the improvement of the water-absorption capacity of the composite flour but decreased its water-retention capacity and its fat-absorption capacity. The fermented composite flour showed better foaming capacity and emulsification capacity than fermented sorghum meal. Fermentation helped to stabilize the foaming properties of the composite flour; however, it did not improve its emulsion stability.